The present invention relates to apparatuses and methods for making (torquing up the connection) and/or breaking (breaking out the connection) joints in drill pipe strings, including systems for spinning pipes (up to the shoulder or to refusal such as for tapered connections).
A number of apparatuses or machines for making and breaking joints in drill pipe strings are known. A superior and commercially successful machine is the HAWKJAW apparatus available from Hawk Industries of Long Beach, Calif. Versions of it are described in U.S. Pat. No. 5,060,542 (Hauk), No. 5,386,746 (Hauk), and No. 5,868,045 (Hauk). The HAWKJAW apparatus (or machine or power tong) including both the HAWKJAW JR. and SR. models, are disclosed in the xe2x80x9cHAWKJAW Operation, Maintenance and Service Manual,xe2x80x9d (Model 100K-ALS-REV 12,99.9200) and xe2x80x9cHAWKJAW Operation, Maintenance and Service Manual, Model 65K-ALS, June 2000.xe2x80x9d (The above-mentioned patents and publications and all other patents and publications mentioned anywhere in this disclosure are hereby incorporated by reference in their entireties.)
Basically, the HAWKJAW apparatus includes a structural frame supporting three wrenches (or jaws or grippers) aligned one on top of the other. The top and bottom wrenches are in the same orientation, and the middle wrench is in a flipped over orientation. Each of the jaws is operated in only one direction and is self-energizing. The HAWKJAW apparatus uniquely allows the drill pipe string to be made up (torqued up) and to be broken out using the same machine and without having to reposition the wrenches relative to the frame for the different operations. Further, a spinner can be provided at the top of the frame to spin the top pipe section out of the drill pipe string once the wrenches have broken the joint connection. In other words, the HAWKJAW apparatus is a device to connect and disconnect drill pipe on the rig floor while tripping, and/or to make and break other connections on the drill rig floor, including small, big and short connections. It is a versatile system. The spinner spins the connection to the shoulder so that the wrenches can take over and torque it up. And, after the connection has been subsequently broken by the wrenches, the spinner can spin it out at low torques to disconnect it.
On the make-up cycle of the HAWKJAW apparatus the structural frame moves about the centerline of the drill pipe string, approximately fifty degrees. This movement is due to the fact that the middle wrench is gripped on the bottom section of the drill pipe string that is rigid to the well. The torque cylinder is hooked to the middle wrench that is gripped on the bottom connection. The top wrench is gripped on the top connection and must turn, and is part of the infrastructure of the HAWKJAW apparatus. As the middle wrench is gripped, it stays rigid on the bottom connection, and the HAWKJAW apparatus (or more specifically the structural frame thereof) which is gripped on the top connection, rotates as the drill pipe is making up. The bottom section of the pipe is not moving; it can be generally 6,000 to 10,000 or so feet below it and thus is rigid in the derrick and does not turn. The only thing that turns is the top connection of the drill pipe string.
When the drill pipe string is being made up, the top connection is rotated clockwise as viewed from above. The torque cylinder rod end is rotatably hooked to the middle wrench, and the body end trunnion is rotatably hooked to the top and bottom wrench frame. As stated above, the top and bottom wrenches are oriented in the same direction, while the middle wrench is flipped over upside down and rotated in the opposite direction.
The torquing load is placed on the middle wrench and either the top or bottom wrench by the hydraulic torque cylinder. Thus, in the making-up operation the middle wrench is connected to the bottom section of the pipe, which is fixed, and with the torque applied between the structural frame of the HAWKJAW apparatus and the fixed middle wrench, the structural frame with the top wrench connected thereto rotates about the centerline of the drill pipe string. In contrast, in the break-out operation the middle wrench is connected to the upper pipe section and the bottom wrench is connected to the lower pipe section. The torquing cylinder applies a load between the middle and bottom wrenches and the middle wrench turns the upper pipe section. The structural frame does not thereby rotate around the centerline of the drill pipe string.
If a torque extension does not completely torque one pipe relative to the other, it is then necessary to torque the apparatus again. This means that when the first torque extension is complete, the apparatus comes off of the pipe; and because it is hung rearward of the pipe it will swing back to its normal free hanging position. The workmen then must push the apparatus back onto the pipe and again initiate the gripping and torquing procedures. This is time consuming, labor intensive and potentially dangerous.
The need for additional torque cycles to properly torque the connection for the drill pipe is especially significant with the HYDRIL pipe which has a wedge thread, providing a tapered drill pipe connection for the joint tool connection. Thus, as the two pieces of pipe are screwed together, the interference fit therebetween becomes progressively tighter. It takes more than fifty degrees to torque this wedge-type thread and more particularly, takes anywhere from one hundred and fifty to one hundred and seventy-five or two hundred degrees to torque the connection out. In contrast, a normal connection needs a torque of thirty-five to forty degrees to make up. Thus, three to six time-consuming grip-torque-release cycles are required to make the HYDRIL pipe with the prior art HAWKJAW apparatus.
Also known in the prior art are different devices for spinning or rotating one pipe relative to another during the making or breaking of the threaded connection between them. An example of a commercially successful product is the SPINMASTER spinner also available from Hawk Industries. The SPINMASTER series of pipe spinners is available in air and hydraulic models, and include a unique gripping system. An example is the SPINMASTER Model 550/950 series, which is easy to maintain since it includes external mounted bearings with removable caps, cylinders pinned in position for simple removal and repair, and few moving parts. Another feature thereof is the high torque output because of the scissor case design with perpendicular mounted cylinders which increase the gripping force and because there is essentially no chain slippage. The chain is a heavy-duty, durable roller-type chain. The compact light design of this spinner makes it easy to be handled on the floor reducing crew fatigue. The basic function and construction of the SPINMASTER spinner are disclosed in U.S. Pat. No. 4,843,924 (Hauk).
The chain for the spinner is periodically lubricated by the workmen by brushing it with grease. This is an ineffective lubricating method, however, since the grease does not get on the insides of the pins and the chains. Additionally, it is a separate labor step and the workmen may forget or procrastinate doing it. And it is especially important to keep the chain oiled in today""s drilling environments, which are frequently subject to corroding salt water air. The linkages if not oiled will wear and rust quickly and bind.
Many of the inventions herein are directed to remedying the problems discussed above. The pipe making and breaking apparatus disclosed herein preferably includes three pipe gripping wrenches, as described the HAWKJAW apparatus above and incorporated in this invention summary. When the apparatus is in the xe2x80x9cmakexe2x80x9d mode the middle wrench is gripped on the bottom pipe section and the top wrench is gripped on the top section, and when in the xe2x80x9cbreakxe2x80x9d mode the bottom wrench is on the bottom section and the middle wrench is on the top pipe. (Alternatively, the middle and top wrenches can be mirror images of the orientations as disclosed herein and the middle wrench can be flipped over compared to the orientation disclosed. Then the middle and top wrenches will be used for break and the middle and bottom for make.) A novel xe2x80x9cgrip holdxe2x80x9d function is provided by the present invention such that when a detented grip hold button (or the like) is pushed, as by the machine""s operator, to its xe2x80x9conxe2x80x9d position the wrench on the bottom pipe section remains gripped during the number of needed torquing operations of the wrench on the upper pipe section, because of a unique pneumatic/hydraulic system. The grip hold button (or lever, switch or other type of actuator) when actuated holds the bottom wrench on the break cycle and the middle wrench in the make cycle. The grip button holds the middle wrench on the break cycle and the top wrench on the make cycle. When the grip hold button is de-energized, the grip button is rendered inoperative.
The chain spinner, which can be part of this make/break apparatus or a separate unit, includes a unique chain oiler system. The spinner for example can be a free hanging, separate stand alone unit. The chain oiler is powered by fluid passing through the spinner motor. When the spray button is pressed the nozzle sprays hydraulic fluid onto the moving chain. The oil can thus only be sprayed when the spinner motor is turning and the chain is moving. Additionally, a chain guide is provided for the spinner chain to prevent the chain from bunching up and catching on the sprockets, which is a serious problem in the prior art. This chain guide is another invention disclosed herein. These chain oilers and guides can be adapted to fit on today""s spinners including the SPINMASTER spinner.
Other objects and advantages of the present invention will become more apparent to those persons having ordinary skill in the art to which the present invention pertains from the foregoing description taken in conjunction with the accompanying drawings.